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olga nikolaevna [1]
3 years ago
13

Solve A=3.14r2 solve for r

Mathematics
1 answer:
VashaNatasha [74]3 years ago
7 0

Step-by-step explanation:

A=3.14r^2

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A statistics practitioner in a large university is investigating the factors that affect salary of professors. He wondered if ev
Ulleksa [173]

Answer:

Step-by-step explanation:

Hello!

Given the linear regression of Y: "Annual salary" as a function of X: "Mean score on teaching evaluation" of a population of university professors. It is desired to study whether student evaluations are related to salaries.

The population equation line is

E(Y)= β₀ + β₁X

Using the information of a n= 100 sample, the following data was calculated:

R²= 0.23

                Coefficient    Standard Error  

Intercept    25675.5           11393

x                  5321                  2119

The estimated equation is

^Y= 25675.5 + 5321X

Now if the interest is to test if the teaching evaluation affects the proffesor's annual salary, the hypotheses are:

H₀: β = 0

H₁: β ≠ 0

There are two statistic you can use to make this test, a Student's t or an ANOVA F.

Since you have information about the estimation of  β you can calculate the two tailed t test using the formula:

t= \frac{b - \beta }{\frac{Sb}{\sqrt{n} } } ~t_{n-2}

t= \frac{ 5321 - 0 }{\frac{2119}{\sqrt{100} } } = 25.1109

The p-value is two-tailed, and is the probability of getting a value as extreme as the calculated t_{H_0} under the distribution t_{98}

p-value < 0.00001

I hope it helps!

3 0
3 years ago
The half-life of a radioactive substance is one day, meaning that every day half of the substance has decayed. Suppose you have
Olegator [25]

Answer:

i wanna say A, but i am unsure...

Step-by-step explanation:

8 0
3 years ago
I need help with geometry
Aleonysh [2.5K]

9514 1404 393

Answer:

  C.  26

Step-by-step explanation:

The two marked angles are "vertical angles." They are congruent.

  x +20 = 3x +8 . . . . . congruent angles have the same measure

  12 = 2x . . . . . . . . . subtract x+8 from both sides

  6 = x . . . . . . . . . divide by 2

  ∠PTQ = (x+20)° = (6+20)° = 26°

7 0
3 years ago
Read 2 more answers
The function below represents the annual interest Alexander earns on a savings account. Identify the term that represents the am
lisabon 2012 [21]

Answer:

Option 4

The term that represents the amount of time that the money is accruing interest is 'x'.

Step-by-step explanation:

Given : The function below represents the annual interest Alexander earns on a savings account.

f(x)=500(1+0.02)^x

To find : Identify the term that represents the amount of time that the money is accruing interest ?

Solution :

The general annual interest formula is A=P(1+r)^t

Where, A is the amount

P is the principal

r is the interest rate

t is the time

The annual interest Alexander earns on a savings account is

f(x)=500(1+0.02)^x

Comparing with general formula,

t=x

The term that represents the amount of time that the money is accruing interest is 'x'.

Therefore, Option 4 is correct.

4 0
4 years ago
Read 2 more answers
Divide 42,847 by 9 and express the quotient<br> as a mixed number
Mamont248 [21]

Answer: 4760\frac{39}{50}

Step-by-step explanation:

4 0
3 years ago
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